« on: August 15, 2015, 02:57 PM »
IOW, to magnetically 'polarize' solid rock by temporarily transforming it into a molten state in the presence of a magnetic field, which is neither practical nor feasible for Mars.-bit (August 14, 2015, 05:54 PM)
I wouldn't be too sure of this. A sufficient quantity of nuclear devices detonated at once would result in glassing of the planet's surface, creating the necessary semimolten state to allow the iron particles to align to a suitable magnetic field.
The question then becomes how did earth gets its magnetic field in the first place, since that would probably lead to clues in how you would generate a planetary magnetic field in order to initially charge up the martian crust.
Without the charged particle deflection offered by a properly aligned magnetic field, the atmosphere just gets blown away. Using machinery to just replace it nonstop would result in the planet slowly but surely losing mass.
It is also possible to magnetize iron by way of impact. Vibrations will disrupt the crystalline structure of the metal enough to allow for magnetic polarity alignment, and this can happen through almost any method of making a piece of steel vibrate.
What if a comet crashed to earth at some point in the past that happened to be mostly iron with a pretty strong field? The impact energy would have made earth's surface hot, and the seismic waves of the impact would have vibrated the earth's crust. If that comet was magnetic, the whole planet would have become magnetic basically overnight.